A senior Palestinian delegation has held talks in Washington with Secretary of State Colin Powell - the first high-level meeting between US and Palestinian officials for months.

We get our legitimacy from President Arafat and the Palestinian Authority

Chief negotiator Saeb Erekat

Afterwards, Mr Powell announced moves to alleviate the humanitarian situation in the West Bank and Gaza, and hinted at new moves to get an agreement on security co-operation.

The talks came as a tentative agreement over a phased Israeli withdrawal from Palestinian areas appeared to have collapsed.

Shortly after discussions between the two sides ended, Israeli troops swept into Gaza and Prime Minister Ariel Sharon said he had no intention of holding peace negotiations with the current Palestinian leadership.

The BBC's Jon Leyne in Washington says relations between the US and the Palestinians remain very frosty.

In a speech in June, US President George W Bush called for the removal of Palestinian leader Yasser Arafat.

Small steps

On Thursday, the Palestinians were not given the usual treatment reserved for honoured guests - the delegation got no police escort, for example.

The Palestinian delegation insists Arafat is legitimate

No big agreements were announced. But the two sides are doing detailed work on security and on the humanitarian situation in the West Bank and Gaza.

Mr Powell said a senior UN official, Catherine Bertini, would be travelling to the region to assess the need for assistance.

What both the Americans and the Palestinians are looking for is progress on a plan under which the Palestinians would progressively take over security as the Israelis withdraw their forces.

The director of the Central Intelligence Agency, George Tenet, is due to meet Palestinian officials on Saturday.

On the issue of Mr Arafat, chief Palestinian negotiator Saeb Erekat pointedly said that his delegation were not "freelancers".

"We get our legitimacy from our president, President Arafat, and the Palestinian Authority," Mr Erekat said.

Stalemate

The talks are due to continue on Friday.

Sharon spoke tough

The Palestinian delegation is expected to ask Washington to help get a scheme for a phased Israeli withdrawal working.

Under the so-called "Gaza-first" plan, Israel would pull out of some territories in return for an end to attacks on Israeli targets.

Earlier in the week, there appeared to be an agreement between Israelis and Palestinians on the issue.

But later Palestinian officials accused Israel of changing the terms of the plan.

As political moves to find solutions to the crisis continued, there was little progress on the ground.

Military moves

In a televised speech, Israeli Prime Minister Arial Sharon dismissed the Palestinian Authority as a "gang of murder".

Israeli tanks destroyed more homes on Thursday

"The only way to peace is to remove this murderous posse from its political position," he said.

The speech came after Israeli tanks and armoured vehicles moved into the Gaza Strip town of Beit Lahiya for the second time in two days.

Hundreds of residents threw stones at the Israeli forces, who opened fire, Palestinian sources said, killing a 17-year-old youth and wounding several other people.

Israeli bulldozers tore down hundreds of trees and destroyed crops before pulling back after two hours.

In the West Bank, troops destroyed four homes - two belonging to two suicide bombers, one to a man who supplied explosives for an attack, and the fourth to a Palestinian militant accused of involvement in attacks against Israel.